In the name

of

Allah

Database Management

Systems

Lecture -2

An overview of lecture - 1

• Database definitions• Database history• File processing systems

– Shortcomings• Advantages of database approach

What we are going to study

next?

• More advantages of database approach

• Disadvantages• Data, its levels• Database users• Some common terms

Lecture Overview

Other Advantages Data consistencyBetter data securityImproved data standards

Balancing of conflicting requirements

Faster development of new applications

Better data accessibility

They also provide

• Economy of scale

• Better control concurrency

• Better backup and recovery procedures

They also provide

BUTIts not always just

theSUGAR

Disadvantages• Higher costs

• Conversion cost

• More difficult recovery

Summary of DB Pros n Cons

• A very useful approach for data processing Provide a

???

Data As ResourceResource

Any asset that is of value to an organization and that incurs cost

Is DataA Resource ? ? ?

Data As Resource

Levels of Data• Real-world data• Metadata• Data Occurrence

Database Users• Application Programmers• End Users

– Naïve– Sophisticated

Database Users• Database Administrator (DBA)

A person who has central control over data and programs that access this data

Functions of DBASchema definitionGranting data access

Functions of DBARoutine Maintenance

BackupsMonitoring disk spaceMonitoring jobs running

Data, Database, Data Model and DBMS

Database

DBMS“How” to get

Application Programs

“What” to get

End usersinteract

Application Programmers

Database Administrators

Database Designers

develop

maintain

design

Software

Users

Data

LOOK we are approaching

THE END

Common Terms • Data • Information• Database Management system

(DBMS)

Common Terms • Data: Facts concerning things, such as

people, objects, or events

Common Terms • Information: Data that have been processed

and presented in a form suitable for human interpretation

Data, Information and Knowledge

Data Information Knowledge &Customer Insight

Tahira

Amir

Jahangir

Ted Martin

Amex G

old

50,0

00

234wireless

B.A.

Amir MohsinTahira

Jahangir

50,00046,800 29,20075,500

ShoesScarvesJewelry

Groceries

shoes

MoUQty

IncomeEducation

Database Queries ?

Amir is mostlikely to buy new product

Tahira is profitablecustomer and is likely to switch carriers

DBMS:A software that handles all access to the database

Common Terms

DBMS:A software that is responsible for applying the authorisation checks and validation procedures

Common Terms

Database Management

Systems

Lecture -2